Objectives: Summer intermittent sun exposure is a major risk factor for melanoma. Socioeconomic position, cognitive and psychosocial factors play a role in sun protection behaviors but the underlying mechanisms are unknown. This study aimed to measure the influence of educational level on sun protection behaviors in French summer vacationers on the Mediterranean coastline, and to identify the mediating psychosocial factors in this pathway. Methods: In summer 2019, French vacationers aged 12-55 staying in coastline campsites were asked about their holiday sun protection behaviors, their knowledge, attitudes, perceived control, and social norm relative to sun protection. A structural equation model measured the direct and indirect effects of educational level on protection behaviors via cognitive and psychosocial factors. Results: Sun protection during vacation increased with educational level. Theoretical knowledge partially mediated this association, from 22% to 86%, particularly for intermediate educational levels. Conclusion: Our results highlight the importance of implementing suitable sun prevention interventions for vacationers, especially those with a lower socioeconomic position. Improving theoretical knowledge around sun protection may be an important part of broader efforts to encouraging improved preventive behaviors.